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本文以钻孔资料为主,并采集大量样品进行了孢子花粉和微体古生物分析,用放射性碳法测定了部分地点的地质年龄,建立了本区全新世地质年表,恢复了北京平原近万年来自然环境演变的基本轮廓。由于地层中普遍含有埋藏泥炭及淤泥沉积,为全新世地层的划分,对比提供了依据,北京地区全新世地层可分为:(1)古全新世长沟组(年龄约12,000—8,000年),(2)早全新世尹家河组(年龄约8,000—6,000年),(3)中全新世尹各庄组(年龄约6,000—2,000年),(4)晚全新世刘斌屯组(年龄为2,000年—现在)。
In this paper, the drilling data, and a large number of samples collected for spore pollen and micro-paleontology analysis, using radioactive carbon method to determine the geologic age of some locations, established the Holocene geological chronology in this area, restored nearly 10,000 Beijing Plain The basic outline of the evolution of the natural environment over the past year. The Holocene strata in the Beijing area can be divided into (1) the Paleocene Changgou Formation (about 12,000-8,000 years old), the Holocene Cretaceous (2) the Early Holocene Yinjiahe Formation (age about 8000-6000), (3) the Middle Miocene Yunggezhuang Formation (aged about 6000-2000), the Late Holocene Liu Bintun Formation (aged 2,000 years -just now).